I had the exact same problem...but when I went to clean and test the IAC I fried it by mistake...so I had to put a new one on. This was 2 weeks ago!
No more cold start hesitation....however...it's starting to rear it's ugly head again, ever so slighty..... and it looks like it may be getting worse.
Keep an eye on it over these next couple weeks and update this post if it changes. I am really curious if your cold start problems come back!
GO BABY GO! 
